Raypak 88AR-398A Manual

INSTA ATION & OPERATING
INSTRUCTIONS
Catalog No. 1000.66 Effective: 06-01-16 Replaces: 12-08-15 P/N 241556 Rev. 3
AVERTISSEMENT: Assurez-vous de bien suivre
les instructions données dans cette notice pour
réduire au minimum le risqué d’incendie ou
d’explosion ou pour éviter tout dommage matériel,
toute blessure ou la mort.
FOR YOUR SAFETY: Do not store or use gaso-
line or other flammable vapors and liquids or other
combustible materials in the vicinity of this or any
other appliance. To do so may result in an explo-
sion or fire.
WHAT TO DO IF YOU SME GAS:
Do not try to light any appliance.•
Do not touch any electrical switch; do not use•
any phone in your building.
Immediately call your gas supplier from a•
neighbor’s phone. Follow the gas supplier’s
instructions.
If you cannot reach your gas supplier, call the•
fire department.
Installation and service must be performed by a
qualified installer, service agency or the gas suppli-
er.
Models 88AR–398A
Type H
CUS
®
WARNING: If the information in these instructions
are not followed exactly, a fire or explosion may
result causing property damage, personal injury or
death.
Ne pas entreposer ni utilizer d’essence ou ni
d’autres vapeurs ou liquids inflammables à proim-
ité de cet appareil ou de tout autre appareil.
CE FAIRE SI VOUS SENTEZ UNE ODEUR
DE GAS:
Ne pas tenter d’allumer d’appareil. •
Ne touchez á aucun interrupteur; ne pas vous•
server des téléphones se trouvant dans la
bâtiment.
Appelez immédiatement votre fournisseur de•
gaz depuis un voisin. Suivre les instructions
du fournisseur.
Si vous ne pouvez rejoinder le fournisseur,•
appelez le service es incendies.
L’installation et l’entretien doivent être assurés par
un installeur qualifié ou par le fournisseur de gaz.
®

2
Rev. 3 reflects the following:
Changes to: Minor changes to pages 8, 17, 22, 29, 37, 38, 39, 40, 52, 55, 58, 59, 66 and 67. Updated Wiring Diagram
on page 47.
Additions: Information under Condensate Management on page 37.
Deletions: Information under Ignition Control Functions on page 39.

3
WARNINGS 4
Pay Attention to These Terms 4
BEFORE INSTA ATION 5
Product Receipt 5
Model Identification 6
Ratings and Certifications 6
Installations at Elevation 6
Component Locations 7
General Information 7
BOI ER DIMENSIONS 8
Time/Temperature Relationships
in Scalds 9
INSTA ATION 9
Installation Codes 9
Equipment Room 10
Clearances 10
Combustion and Ventilation Air 11
Direct Vent 14
Conventional Combustion Air Supply 14
Water Piping 15
Hydronic Heating 16
System Sensor Installation 16
Applications and Modes 17
Heater Flow Rates and Pressure Drops 17
MODE 1 Water Plumbing 18
MODE 2 Water Plumbing 19
MODE 3 Water Plumbing 20
Gas Supply 21
Gas Supply Connection 21
Equivalent Pipe Length 21
Gas Supply Pressure 22
Electrical Power Connections 22
Making the Electrical Connections 23
Field Wiring Connections 24
Heating System Sensor Installation 25
Venting 28
Venting Installation Tips 31
Venting Configurations 31
Condensate Management 37
Freeze Protection 38
Controls 39
Outdoor Reset Concept 45
WIRING DIAGRAM 47
Converting Natural to Propane Gas 48
Gas Valve & Combustion Settings 49
START-UP 50
Pre Start-up 51
Pre Start-up Check 51
Initial Start-up 51
Preparation 51
Start-Up 52
Lighting Instructions 54
To Turn Off Gas to Appliance 54
TROUB ESHOOTING 55
XPak FT Error Codes 55
Heater Errors 55
Heater Faults 55
Sensor Resistance Values 55
XPak FT Fault Text 56
MAINTENANCE 58
Suggested Minimum
Maintenance Schedule 58
Preventive Maintenance
Schedule 58
Combustion Chamber Cleaning
Instructions 60
APPENDIX 61
Inside Air Contamination 61
Important Instructions for the
Commonwealth of Massachusetts 62
WARRANTY 63
START-UP CHECK IST 64
I USTRATED PARTS IST 65
CONTENTS

4
DANGER: Indicates the presence of immediate hazards which will cause severe
personal injury, death or substantial property damage if ignored.
WARNING: Indicates the presence of hazards or unsafe practices which could cause
severe personal injury, death or substantial property damage if ignored.
CAUTION: Indicates the presence of hazards or unsafe practices which could cause
minor personal injury or product or property damage if ignored.
NOTE: Indicates special instructions on installation, operation, or maintenance which
are important but not related to personal injury hazards.
WARNINGS
Pay Attention to These Terms
DANGER: Make sure the gas on which the boiler
will operate is the same type as that specified on the
boiler rating plate.
WARNING: Should overheating occur or the gas
supply valve fail to shut, do not turn off or disconnect
the electrical supply to the boiler. Instead, shut off
the gas supply at a location external to the boiler.
WARNING: Do not use this boiler if any part has
been under water. Immediately call a qualified
service technician to inspect the boiler and to
replace any part of the control system and any gas
control which has been under water.
WARNING: To minimize the possibility of improper
operation, serious personal injury, fire, or damage to
the boiler:
• Always keep the area around the boiler free of
combustible materials, gasoline, and other
flammable liquids and vapors.
• oiler should never be covered or have any
blockage to the flow of fresh air to the boiler.
WARNING - CA IFORNIA PROPOSITION
65: This product contains chemicals known to the
State of California to cause cancer, birth defects or
other reproductive harm.
WARNING: Risk of electrical shock. More than one
disconnect switch may be required to de-energize
the equipment before servicing.
WARNING: UL-recognized fuel gas detectors are
recommended in all enclosed propane and natural
gas applications wherein there is a potential for an
explosive mixture of fuel gas to accumulate and their
installation should be in accordance with the
detector manufacturer's recommendations and/or
local laws, rules, regulations, or customs.
WARNING: oth natural gas and propane have an
odorant added to aid in detecting a gas leak. Some
people may not physically be able to smell or
recognize this odorant. If you are unsure or
unfamiliar with the smell of natural gas or propane,
ask your local gas supplier. Other conditions, such
as "odorant fade," which causes the odorant to
diminish in intensity, can also hide, camouflage, or
otherwise make detecting a gas leak by smell more
difficult.
WARNING: This appliance produces condensate
from the flue products that is acidic and highly
corrosive. Raypak recommends the use of a
condensate neutralizer kit to avoid long-term
damage to the drainage system and to meet local
code requirements.
WARNING: Vent connectors serving any other
appliances shall not be connected into any portion of
mechanical draft systems operating under a positive
pressure. If an XPak FT®boiler is installed to replace
an existing unit, the vent system MUST be verified to
be of the correct size and of one of the Category IV
vent materials identified in this manual. If it is NOT,
it MUST be replaced.

5
BEFORE INSTA ATION
Raypak strongly recommends that this manual be reviewed thoroughly before installing your XPak FT boiler.
Please review the General Safety information before installing the unit. Factory warranty does not apply to units
that have been improperly installed or operated. (Refer to the warranty at the back of this manual.) Installation
and service must be performed by a qualified installer, service agency or gas supplier. If, after reviewing this
manual, you still have questions which this manual does not answer, please contact your local Raypak repre-
sentative or visit our website at www.raypak.com.
Thank you for purchasing a Raypak product. We hope you will be satisfied with the high quality and durability of
our equipment.
Product Receipt
On receipt of your unit it is suggested that you visually check for external damage to the shipping carton. If the
carton is damaged, make a note to that effect on the ill of Lading when signing for the shipment. Next, remove
the boiler from the carton. Report any damage to the carrier immediately.
On occasion, items are shipped loose. e sure that you receive the correct number of packages as indicated on
the ill of Lading.
Claims for shortages and damages must be filed with the carrier by consignee. Permission to return goods must
be received from the factory prior to shipping. Goods returned to the factory without an authorized Returned
Goods Receipt number will not be accepted. All returned goods are subject to a restocking charge.
When ordering parts, you must specify the model and serial number of the boiler. When ordering under warranty
conditions, you must also specify the date of installation.
Purchased parts are subject to replacement only under the manufacturer’s warranty. Debits for defective
replacement parts will not be accepted. Parts will be replaced in kind only per Raypak’s standard warranties.
NOTE: Minimum 18 AWG, 105°C, stranded wire
must be used for all low voltage (less than 30 Volts)
external connections to the unit. Solid conductors
should not be used because they can cause
excessive tension on contact points. Install conduit
as appropriate. All high voltage wires must be the
same size (105°C, stranded wire) as the ones on the
unit or larger.
CAUTION: This boiler requires forced water
circulation when the burner is operating. See
minimum and maximum flow rates. Severe damage
will occur if the boiler is operated without proper
water flow circulation.
AVERTISSEMENT: En cas de surchauffe ou de
non fermeture de la vanne d’alimentation en gaz,
n’éteignez ou ne débranchez pas l’alimentation élec-
trique de la chaudière. Coupez plutôt l’alimentation
en gaz á l’extérieur de la chaudière.
NOTE: When the boiler has been filled for the first
time or the system has been drained and refilled, it
will be necessary to release any air that may have
become trapped within the appliance heat
exchanger. Open the bleedle valve until all air is
purged.
AVERTISSEMENT: N’utilisez pas cette Chaudière
si une partie de celle-ci s’est retrouvée sous l’eau.
Appelez immédiatement un technician de service
qualifié pour inspecter la Chaudière et pour
remplacer toute partie du système de contrôle et
toute commande de gaz s’étant retrouvée sous
l’eau.

6
Model Identification
The model identification number and boiler serial num-
ber are found on the rating plate located on the inside
upper right panel and also on inlet air decal. The
model number has the form H7-198AR or similar
depending on the unit size and configuration. The let-
ter in the first group of characters identifies the
application (H = Hydronic Heating). The number which
follows identifies the firing mode (7 = electronic mod-
ulation). The second group of characters identifies the
size of the unit (three numbers representing the
approximate M TUH input), and, where applicable, a
letter indicating the manufacturing series.
Ratings and Certifications
Standards:
• ANSI Z21.13 · CSA 4.9 - latest edition, Gas-
Fired Hot Water oilers
• SCAQMD Rule 1146.2
All units are National oard Registered, and design-
certified and tested by the Canadian Standards
Association (CSA) for the U.S. and Canada. Each boil-
er is constructed in accordance with Section IV of the
American Society of Mechanical Engineers (ASME)
oiler and Pressure Vessel Code and bears the ASME
“H” stamp. This boiler also complies with the latest edi-
tion of the ASHRAE 90.1 Standard.
Installations at Elevation
Rated inputs are suitable for up to 2,000 ft elevation
without de-rating. Consult your local representative or
the factory for installations at altitudes over 2,000 ft
above sea level. No hardware changes are required
to the boilers for installations up to 10,000 ft (adjust-
ments may be required).
Fig 1: Boiler Carton Contents
Items Included:
1. (1) XPak FT oiler
2. (1) Wall Mount racket
3. (6) Lag Screws
4. (2) Hold Down rackets
5. (6) Washers
6. (1) Full-Scale Heater Template
7. (1) T & P Gauge
8. (1) Condensate Trap & Hose
9. (2) System Sensor
10. (1) Outdoor Sensor
11. (1) Installation & Operating Instructions Manual
12. (1) Propane Orifice Kit (Models 88AR & 108AR
ONLY)
WARNING: Altering any Raypak pressure vessel
by installing replacement heat exchangers or any
ASME parts not manufactured and/or approved by
Raypak will instantly void the ASME and CSA ratings
of the vessel and any Raypak warranty on the
vessel. Altering the ASME or CSA ratings of the
vessel also violates national, state, and local
approval codes.

7
Component ocation
Fig 2: Component ocations
General Information
Model
No.
AFUE Rating Minimum
Operating
Input
(MBH)
Water
Conn.
(NPT)
Gas conn. (NPT) Vent Size (inches)
Input (MBH) % Nat Pro Flue Intake
Min Max
88AR 17.0 85 95 12.0 1” ½” ½” 2”/3”** 2”/3”**
108AR 22.0 110 95 13.0 1” ½” ½” 3” 3”
198AR 39.8 199 95 28.4 1-1/4” ¾” ¾” 3” 3”
278AR 55.0 275 95 36.6 1-1/4” ¾” ¾” 3” 3”
398A 39.9 399 96* 39.9 1-1/2” ¾” ¾” 3”/4”*** 3”/4”***
Table A: Basic Data
*Model 398A value is a Thermal Efficiency.
**Model 88AR has a 3" standard vent size, but can be reduced to 2" with a shorter run. (See page 31 for details)
***Model 398A has a 4" standard vent size, but can be reduced to 3" with a shorter run. (See page 31 for details)

8
Dimensions
B
P
L
J
D
N
M
F
A
C
H
E
D
3.79
KF
WATER INLET
GAS SUPPLY CONNECTION
WATER OUTLET
CONDENSATE
OUTLET
AIR INLET
PRV
FLUE OUTLET
5.6 6.0
Fig 3: Boiler Dimensions
Model
No.A B C D E F H J K M N P
88AR/
108AR 16.4 35.8 16.5 2.1 2.7 6.3 7.8 9.5 5.5 1.5 4.6 2.8 2.3
198AR/
278AR 18.6 36.2 19.4 2.0 3.1 8.2 10.0 11.3 7.1 1.7 12.3 3.6 2.3
398A 21.4 38.6 22.1 2.7 4.0 10.1 12.0 13.0 8.9 2.6 15.3 4.0 2.1
Table B: Basic Data

9
Model No. Boiler Water Volume
(gallons)
88AR 3.2
108AR 2.9
198AR 5.2
278AR 4.5
398A 5.9
WARNING: This boiler cannot supply hot water for
use by individuals directly. A heat exchanger must
be used in conjunction with this boiler to meet DHW
needs.
Table C: Heater Water Volume
Time/Temperature
Relationships in Scalds
The following chart details the relationship of water
temperature and time with regard to scald injury and
may be used as a guide in determining the safest
water temperature for your applications.
Water Temp. Time to Produce
Serious Burn
120°F More than 5 minutes
125°F 1-1/2 to 2 minutes
130°F About 30 seconds
135°F About 10 seconds
140°F Less than 5 seconds
145°F Less than 3 seconds
150°F About 1-1/2 seconds
155°F About 1 second
Table courtesy of The Shriners Burn Institute
Table D: Time to Produce Serious Burn
INSTA ATION
Installation Codes
Installations must follow these codes:
Local, state, provincial, and national codes, laws,•
regulations and ordinances
National Fuel Gas Code, ANSI Z223.1/NFPA 54 –•
latest edition (NFGC)
National Electrical Code, ANSI/NFPA 70 - latest•
edition (NEC)
Standard for Controls and Safety Devices for•
Automatically Fired oilers, ANSI/ASME CSD-1,
(CSD-1) when required
For Canada only: CAN/CSA 149 Natural Gas•
and Propane Installation Code and CSA C22.1
C.E.C. Part 1 (C22.1)
CAUTION: This boiler should be located in an area
where water leakage will not result in damage to the
area adjacent to the appliances or to the structure.
When such locations cannot be avoided, it is
recommended that a suitable catch pan, adequately
drained, be installed under the appliance. The pan
must not restrict air flow.

10
Equipment Room
Install CO detectors per local regulations. oiler
requires yearly maintenance, see chapter “Checks,
adjustments and fault finding”.
Operating Limits of the boiler:
Max. oiler Outlet Temperature: 200°F (99°C)
Max. Operating Pressure: 80 psi (5.5 bar)
The hot water distribution system must comply with all
applicable codes and regulations. When replacing an
existing boiler, it is important to check the condition of
the entire hot water distribution system to ensure safe
operation.
In addition, the unit shall be installed such that the gas
ignition system components are protected from water
(dripping, spraying, rain, etc.) during appliance opera-
tion or service.
Boiler Side
Min.
Clearances
from
Combustible
Surfaces
Minimum
Service
Clearances
Right Side 0” 1”
Left Side 0” 1”
Top 0” 24”
Front Open 24”
Vent 1” 1”
ottom 6” 12”
Table E: Clearances — Indoor Installations
Clearances
Indoor Installations
When installed according to the listed minimum clear-
ances from combustible construction, these boilers
can be serviced without removing permanent structur-
al construction around the unit. However, for ease of
servicing, we recommend a clearance of at least 24 in.
in front, on the rear and 24 in. above the top of the boil-
er. This will allow the unit to be serviced in its installed
location without movement or removal of the heater.
Service clearances less than the minimum may
require removal of the unit to service either the heat
exchanger or the burner components. In either case,
the boiler must be installed in a manner that will enable
the unit to be serviced without removing any structure
around the boiler.
NOTE: Use of this boiler in construction areas
where fine particulate matter, such as concrete or
dry-wall dust, is present may result in damage to the
boiler that is not covered by the warranty. If operated
in a construction environment, a clean source of
combustion air must be provided directly to the
boiler.
Fig 4: Wall Mount Installation

11
Fig. 5: Minimum Clearances from Combustible
Surfaces
Venting not shown for clarity. oiler must be vented per
instructions in this manual
Combustion and Ventilation Air
This unit must be supplied with sufficient quantities of
non-contaminated air to support proper combustion
and equipment ventilation. Combustion air can be sup-
plied via conventional means where combustion air is
drawn from the area immediately surrounding the boil-
er, or via direct vent, where combustion air is drawn
directly from outside. All installations must comply with
the requirements of the NFGC (U.S.) or 149
(Canada), and all local codes.
CAUTION:Combustion air must not be
contaminated by corrosive chemical fumes which
can damage the boiler and void the warranty. (See
the Appendix.)
NOTE: It is recommended that the intake vent be
insulated in cold climates to minimize sweating.
Fig 6: Indoor Air Duct

12
Fig 7: Two Vertical Air Ducts - Floor Fig 8: Single Air Duct
Fig 9: Two Vertical air Ducts - Ceiling Fig 10: Two Horizontal Air Ducts

13
U.S. Installations
1Canadian Installations 2
A Clearance above grade, veranda, porch,
deck, or balcony 1 ft (30 cm) 1 ft (30 cm)
B Clearance to window or door that may be
opened
4 ft (1.2 m) below or to side
of opening; 1 foot (30 cm)
above opening
3 ft (91 cm)
C Clearance to permanently closed window * *
D
Vertical clearance to ventilated soffit located
above the terminal within a horizontal dis-
tance of 2 ft (61cm) from the centerline of the
terminal
5 ft (1.5 m) *
E Clearance to unventilated soffit * *
F Clearance to outside corner * *
G Clearance to inside corner 6 ft (1.83 m) *
H Clearance to each side of center line ex-
tended above meter/regulator assembly *
3 ft (91 cm) within a height
15 ft above the me-
ter/regulator assembly
I Clearance to service regulator vent outlet * 6 ft (1.83 m)
J
Clearance to non-mechanical air supply inlet
to building or the combustion air inlet to any
other appliance
4 ft (1.2 m) below or to side
of opening; 1 ft (30 cm)
above opening
3 ft (91 cm)
K Clearance to mechanical air supply inlet 3 ft (91 cm) above if within
10 ft (3 m) horizontally 6 ft (1.83 m)
L Clearance above paved sidewalk or paved
driveway located on public property 7 ft (2.13 m) 7 ft (2.13 m) t
M Clearance under veranda, porch, deck or
balcony * 12 in. (30 cm) TT
1 In accordance with the current ANSI Z223.1/NFPA 54 National Fuel Gas Code
2 In accordance with the current CAN/CSA-B149 Installation Codes
t Vent terminal shall not terminate directly above sidewalk or paved driveway located between 2 single-family dwellings that serves
both dwellings
TT Permitted only if veranda, porch, deck, or balcony is fully open on a minimum of two sides beneath the floor and top of terminal and
underside of veranda, porch, deck or balcony is greater than 1 ft (30 cm)
* Clearances in accordance with local installation codes and the requirements of the gas supplier
Fig. 11: Minimum Clearances from Vent/Air Inlet Terminations – Indoor and Outdoor Installations
Table F: Vent/Air Inlet Termination Clearances

14
Direct Vent
If outside air is drawn through the intake pipe directly
to the unit for combustion:
1. Install the combustion air ducting kit.
2. Install combustion air direct vent in accordance
with Fig. 24 (horizontal) or Fig. 26 (vertical) of this
manual.
3. Ventilation of the space occupied by the boiler(s)
is recommended and can be provided by an open-
ing(s) for ventilation air at the highest practical
point communicating with the outdoors. The total
cross-sectional area should be at least 1 in² of free
area per 20,000 TUH (111 mm² per kW) of total
input rating of all equipment in the room when the
opening is communicating directly with the out-
doors or through vertical duct(s). The total
cross-sectional area should be at least 1 in² of free
area per 10,000 TUH (222 mm² per kW) of total
input rating of all equipment in the room when the
opening is communicating with the outdoors
through horizontal duct(s). Damage to the equip-
ment due to inadequate ventilation of the space is
not a warrantable failure.
4. In cold climates, and to mitigate potential freeze-
up, Raypak highly recommends the installation of
a motorized sealed damper on the air intake to
prevent the circulation of cold air through the boiler
during non-operating hours.
Conventional Combustion Air
Supply
U.S. Installations
All Air from Inside the Building
The confined space shall be provided with TWO per-
manent openings communicating directly with an addi-
tional room(s) of sufficient volume so that the com-
bined volume of all spaces meets the criteria for a
room large in comparison (NFGC). The total input of all
gas utilization equipment installed in the combined
space shall be considered in making this determina-
tion. Each opening shall have a minimum free area
of 1 in.2 per 1,000 TUH (2,225 mm2 per kW) of the
total input rating of all gas utilization equipment in the
con- fined space, but not less than 100 in.2 (645 cm2).
One opening shall commence within 12 in. (305 mm)
of the top, and one opening shall commence within 12
in. (305 mm) of the bottom of the enclosure. The mini-
mum dimension of air openings shall be not less than
3 in. (76 mm) in any direction.
All Air from Outdoors
The confined space shall communicate with the out-
doors in accordance with one of the methods below.
The minimum dimension of air openings shall not be
less than 3 in. (76 mm) in any direction. Where ducts
are used, they shall be of the same cross-sectional
area as the net free area of the openings to which they
connect.
1. Two permanent openings, one commencing
within 12 in. (305 mm) of the top, and one com-
mencing within 12 in. (305 mm) of the bottom of
the enclosure, shall be provided. The openings
shall communicate directly, or by ducts, with the
outdoors or spaces (crawl or attic) that freely com-
municate with the outdoors.
a. Where directly communicating with the out-
doors or where communicating to the
outdoors through vertical ducts, each open-
ing shall have a minimum free area of 1 in.2
per 4,000 TUH (550 mm2per kW) of total
input rating of all equipment in the enclosure.
b. Where communicating with the outdoors
through horizontal ducts, each opening shall
have a minimum free area of 1 in.2per 2,000
TUH (1,100 mm2per kW) of total input rat-
ing of all equipment in the enclosure.
2. ne permanent opening, commencing within 12
in. (305 mm) of the top of the enclosure, shall be
permitted where the equipment has clearances of
at least 1 in. (25 mm) from the sides, top and bot-
tom and 6 in. (152 mm) from the front of the
appliance. The opening shall directly communi-
cate with the outdoors or shall communicate
through a vertical or horizontal duct to the out-
doors or spaces that freely communicate with the
outdoors, and shall have a minimum free area of:
a. 1 in.2per 3,000 TUH (740 mm2per kW) of
the total input rating of all equipment located in
the enclosure, and
b. Not less than the sum of the areas of all vent
connectors in the confined space.
WARNING: Do not use the “one permanent
opening” method if the equipment room is under
negative-pressure conditions.

15
Canadian Installations
1. Ventilation of the space occupied by the boiler
shall be provided by an opening(s) for ventilation
air at the highest practical point communicating
with the outdoors. The total cross-sectional area of
such an opening(s) shall be at least 10% of the
area required in 2. and 3. (below), but in no case
shall the cross-sectional area be less than 10 in.2
(65 cm2).
2. For boilers using a barometric damper in the vent
system, there shall be a permanent air supply
opening(s) having a cross section area of not less
than 1 in.2per 7,000 TUH (320 mm2per kW) up
to and including 1 million TUH, plus 1 in.2per
14,000 TUH (160 mm2per kW) in excess of 1
million TUH. This opening(s) shall be either
located at or ducted to a point not more than 18 in.
(450 mm) nor less than 6 in. (152 mm) above the
floor level. The duct can also “goose neck” through
the roof. The duct is preferred to be straight down
and terminated 18 in. (450 mm) from the floor, but
not near piping. This air supply opening require-
ment shall be in addition to the air opening for
ventilation air required in 1. (above).
3. For heaters when air supply is provided by natural
air flow from outdoors for a power burner and
there is no draft regulator, drafthood or similar flue
gas dilution device installed in the same space, in
addition to the opening for ventilation air required
in 1., there shall be a permanent air supply open-
ing(s) having a total cross-sectional area of not
less than 1 in.2for each 30,000 TUH (74 mm2per
kW) of total rated input of the burner(s), and the
location of the opening(s) shall not interfere with
the intended purpose of the opening(s) for ventila-
tion air referred to in 1. This opening(s) can be
ducted to a point not more than 18 in. (450 mm)
nor less than 6 in. (152 mm) above the floor level.
The duct can also “goose neck” through the roof.
The duct is preferred to be straight down 18 in.
(450 mm) from the floor, but not near piping.
4. Refer to the 149 Installation Code for additional
information.
CAUTION: All combustion air must be drawn from
the air outside of the building; the mechanical equip-
ment room must communicate directly with the
outdoors.
Water Piping
General
The boiler should be located so that any water leaks
will not cause damage to the adjacent area or struc-
tures.
Relief Valve Installation and Piping
The boiler is supplied with a Section IV “H” stamped
relief valve sized for the full input of the unit. Relief
valve discharge piping shall provide no less than the
cross-sectional area of the relief valve outlet and must
be routed to a safe point of discharge. Installation must
comply with all national, state and local codes.
Temperature & Pressure Gauge
The temperature and pressure gauge is shipped loose
for field installation and must be installed within 12
inches of the boiler outlet (if possible) in an easily
readable location. Installation must comply with ASME
Section IV as well as all applicable national, state and
local codes.
Hydrostatic Test
Unlike many types of heaters, this boiler does not re-
quire hydrostatic testing prior to being placed in oper-
ation. The heat exchanger is ASME certified for 80 PSI
maximum working pressure. However, Raypak does
recommend hydrostatic testing of the piping connec-
tions to the unit and the rest of the system prior to
operation. This is particularly true for hydronic sys-
tems using expensive glycol-based anti-freeze.
Raypak recommends conducting the hydrostatic test
before connecting gas piping or electrical supply.
WARNING: Care must be taken to ensure that the
equipment room is not under negative pressure
conditions.
NOTE: Refer to the VERSA IC®Applications Guide
(Catalog #5000.72) for detailed instructions regard-
ing the various applications supported by the
VERSA IC control system.
WARNING: Pressure relief valve discharge piping
must be piped near the floor and close to a drain to
eliminate the potential of severe burns. Do not pipe
to any area where freezing could occur. Refer to
local codes.
CAUTION: This boiler requires forced water
circulation when the burner is operating. See Table H
for minimum and maximum flow rates. The pump
must be interlocked with the boiler to prevent heater
operation without water circulation.

16
Leaks must be repaired at once to prevent damage to
the heater. NEVER use petroleum-based stop-leak
compounds.
To perform hydrostatic test:
1. Connect fill water supply. With bleed valve open,
fill boiler with water. When water flows from bleed
valve, shut off water. Close bleed valve. Carefully
fill the rest of the system, making sure to eliminate
any entrapped air by using high-point vents. Close
feed valve. Test at standard operating pressure for
at least 24 hours.
2. Make sure constant gauge pressure has been
maintained throughout test.
3. Check for leaks. Repair if found.
Hydronic Heating
Pump Selection
In order to ensure proper performance of your boiler
system, you must install a correctly-sized pump. Ray-
pak recommends designing for a ∆T within the range
of 20°F to 60°F (8°C to 19°C). See Table H for accept-
able flow rates for each model (∆T is the temperature
difference between the inlet and outlet water when the
heater is firing at full rate).
Three-Way Valves
Three-way valves intended to regulate system water
temperatures by reducing flow in the boiler should not
be used.
Boiler
Model
Standard Boiler Pump*
Pump HP
H7-88AR TACO 007 1/25
H7-108AR TACO 007 1/25
H7-198AR TACO 010 1/8
H7-278AR TACO 012 1/8
H7-398A TACO 012 1/8
Table G: Pump Selection
* Pump selection based on 30° ∆T with up to 50 eq. ft. of tubing.
NOTE: The 50 eq. feet of tubing typically represents
25 linear feet of tubing and 25 eq. feet of fittings.
CAUTION: e careful when installing the drywell
not to over-tighten the well as this can damage the
well and may prevent the sensor from fitting properly.
Fig 12: System Sensor Installation
System
Sensor (S3)
Thermal
Paste
Drywell
NPT
Fitting
System Sensor Installation
The System Sensor (S3) is required for all selectable
modes unless the unit’s firing rate will be controlled by
an external source such as our Temp Tracker MOD+
Hybrid sequencer. Proper placement and method of
installation are critical for proper operation of the sys-
tem. (See Fig. 12) The sensor must be installed in a
drywell in conjunction with heat conductive compound
as shown in the following images. The drywell must be
installed no more than 5 equivalent feet of pipe/tubing
downstream of the de-coupler and installed in such a
way that ensures the sensor bulb is in the flow path.

17
Applications & Modes
The VERSA IC Control system is designed for a wide
range of applications. The installer/design engineer
should refer to the following Modes to determine which
best fits the intended application and functionality for
the unit being installed.
The XPak FT has three modes available to them to
address the various applications the units can be
applied to.
Mode 1
This mode is for hydronic heating systems with single
or multiple boilers (Maximum 4 boilers) in primary/sec-
ondary piping configuration with or without Outdoor Air
Reset (S4). The system temperature is controlled by
the System sensor (S3). The oiler Pump (P1) runs
during any call for heat. The System Pump (P2) runs
whenever the system is enabled for heating and the
outdoor air temperature is lower than the warm weath-
er shut down (WWSD) temperature setting (if utilized).
The oiler Pump and System Pump are delayed “off”
as user-defined in the ADJUST menu. See Fig. 13 for
piping example.
Mode 2
This mode is for hydronic heating systems with single
or multiple boilers (Maximum 4 boilers) in primary/sec-
ondary piping configuration with or without Outdoor Air
Reset (S4) with indirect DHW on the system loop (with
or without priority). The system temperature is con-
trolled by the System sensor (S3). The Indirect DHW
sensor (S5) determines the indirect call/tank setpoint.
The system temperature is boosted to Target Max
when using the Indirect DHW sensor (S5) during an
indirect call for heat. Priority mode toggles off the
System Pump (P2) when an indirect call for heat is
present. The oiler Pump (P1) runs during any call for
heat. The Indirect DHW Pump (P3) runs during an
indirect call for heat with no “off” delay. The boiler
Table H: Heater Rates of Flow and Pressure Drops
Notes: asis for minimum flow is ∆T . asis for maximum flow is GPM.
Model
No.
MAXIMUM
F OW
30°F
∆T
40°F
∆T
50°F
∆T
MINIMUM
F OW
GPM ΔP (ft) ΔT GPM ΔP (ft) GPM ΔP (ft) GPM ΔP (ft) GPM ΔP (ft) ΔT
H7-88A 8.1 5.4 20 5.4 3.3 4.0 2.3 3.2 1.8 2.7 1.4 60
H7-108A 10.5 7.4 20 7.0 4.5 5.2 3.2 4.2 2.4 3.5 2.0 60
H7-198A 18.9 11.6 20 12.6 6.2 9.5 4.3 7.6 3.5 6.3 3.0 60
H7-278A 26.1 20.3 20 17.4 10.1 13.1 6.5 10.5 4.9 8.7 4.0 60
H7-398A 38.3 14.1 20 25.5 7.4 19.2 5.0 15.3 4.0 12.8 3.4 60
Pump (P1) and System Pump (P2) delay “off” as user-
defined in the ADJUST menu. The System Pump (P2)
runs whenever the system is enabled for heating and
the outdoor air temperature is lower than the WWSD
temperature setting (if utilized) unless an indirect call
for heat is present with priority. See Fig. 14 for piping
example.
Mode 3
This mode is for hydronic heating systems with single
or multiple boilers (Maximum 4 boilers) in primary/sec-
ondary piping configuration with or without Outdoor Air
Reset (S4) with indirect DHW on the boiler loop (with
priority). The system temperature is controlled by the
Supply sensor (S3) whenever the indirect call for heat
is not active. The DHW Supply sensor (S5) determines
the indirect call/tank setpoint. During an indirect call for
heat the boiler firing rate is determined by the water
temperature at the Indirect Supply sensor (S6) and the
Target Max setting when using the Indirect DHW sen-
sor (S5).
The oiler Pump (P1) runs during all heat calls regard-
less of priority. The Indirect DHW Pump (P3) runs
during an indirect call for heat with no “off” delay. The
oiler Pump (P1) and System Pump (P2) delay “off” as
user-defined in the ADJUST menu. The system pump
(P2) runs whenever the system is enabled for heating
and the outdoor air temperature is lower than the
WWSD temperature setting (if utilized) unless an indi-
rect call for heat is present. See Fig. 15 for piping
example.
System flow must exceed 120% of boiler flow.
WARNING: All potable water heating with this
boiler must be by an indirect heat exchanger. Only
non-potable water will go through the boiler.
Water Flow Rates

18
Fig 13: MODE 1 - Single Boiler - Primary/Secondary Piping

19
Fig 14: MODE 2 - Single Boiler - Primary/Secondary Piping
with Indirect DHW on System oop

20
Fig 15: MODE 3 - Single Boiler - Primary/Secondary Piping
with Indirect DHW on Boiler oop